Rotary rock disk bit



June 4, 1935. J. WQSPERRY ROTARY ROCK DISK BIT Filed Oct. 4, 1929 2 Sheets-Sheet 1 .ll. IIII. v

[/V l/E/V Toe: James A/ JPseey.

147'7'0 e/vsy.

June 4,1935. J w SPERRY I 1 2,003,793

ROTARY ROCK DISK BIT Filed Oct. 4, 1929 2 Sheets-Sheet 2 [/1/ VE/V 7'0/3 [W755 4 5/ 5? R. x 35/ ATTOZE/Vf).

Patented June 4, 1935 g r I UNITED STATES PATENT DFFICE ROTARY ROCK DIISK BIT James W. Sperry, South Pasadena, Calif.

Application October 4, 1929, Serial No. 397,238

i 4 Claims. (01. 255-11) 9 This invention relates to bits of the character tion will be made evident throughout thefollowemployed in drilling wells by the rotary system ing part of the specification. of drilling, in which a cutting tool is rotated Referring to the drawings which are for illuson the lower end of a vertical drilling shaft trative purposes only, g 5 consisting generally of a string of drill pipe Fig. l is a side elevation of a rotary disk bit 5 extending into the well and rotated by rotary of the invention-V apparatus situated at the top of the well. s- 2 s a pa y ti n d fr nt l vat n e n In the rotary method of drilling wells, cutresponding to gting away or displacement of the subterranean 3 is a horizontal cross Sootion l kin ps formations is accomplished by one or the other we from the p a d d' y the e,3 10

of, or the combination of, two operations which of p are: first, a scraping or slicing operation, such ig. 4 is an enlarged frag y Cross n as produced by the fist-tail bit, and second, a on a plane p t d y th l e 4 of F pounding or crushing operation, such as accom- 5 is an vat V w o af o t o ushed by rock bits having toothed rollers which a cutter di having an alternative form f te th roll in engagement with the formation, of the character comprehended by the invention.

It is an object of the invention to provide 'oi partly sectioned elevational i a new form of disk bit which may be employed 1 to 2, but Showing an a t at o m,

to cut hard formations and which is so designed of myiilvention- 1 that a combined impact and slicing operation 7 is a p y c ed eleliational view 20 is accomplished by th di k tt th i similar to Fig. 2, showing an alternative form of A further object of the invention is to prom dovioo in which a Supporting r o c r ul vide a rotary disk bit having a simple and, cross section is employed and in which thebear rugged bit body consisting essentially of a single members are preve from rotation y become displaced and lost in the well. body- I 1 V A further object of theinvention is to provide 7 o Simple m me t of my i ve as r a disk bit of this character with simple means illustrated y Figsand 3, I p oy b for removably supporting the replaceable cutter y having an pp b y portion a unitary structure having no parts which may te -engagement with the vertical legs of the drill 1151; and utter disk be i gs. equipped with means, such as a threaded pin I3, 30 i A further object .of the invention is to protaching the bit body H to the ow e vide a bit of this character having a central of String o drill p po, there being a supporting leg and having a fluid passage ex opening oXtohdihg downwardly f p 10f tending vertically and centrally through said t e th ad d D l3 and into the body l fo m 5 supporting leg so as to deliver a fluid, such as a main fluid chamber orpassage I; which comthe mud and water mixtures employed in rotary municates with the interior of the drill pipe to drilling, against the central core formed by the which t body is tt ,Th bit, body disk h w n i p t o as to remove H has a center leg I5 and side legs 16 which ex asslst m removmg Such a 9 tend downwardly and preferably vertically there 40 further ObJePt of the Invention to from, as best shown in Fig. 2, these legs being so 2 233 iggg f ia g i giggitfifi; spaced that cutter channels or spaces I! are supporting bar of non-circular cross section exfoimsdibibween'mg (gamer leg and h Side legs tending through and supported in the lower end. 31 extendme h openings 20- in 5 of said legs, and bearing members having noncircular openings therein positioned sov as to @Tugged supportmg bar Whlch lsnen-clrtular' hold said bearing members on the supporting cross Sectlon 50 as to be eb e n h I bar in a desired axially offset co-relationship. openings 20 which are'also non-circular in Cross In the practice of the invention I may support section. AS Shown in Fig. 1, I prefer to'mak'e the and near the lower ends of the legs l5 and I6.

the bearing members non-rotatably on'a supbar 2| of hexagonal cross sectionand tofm'ake 50 porting bar of circular cross section by proopenings 20 of the l s l5 i h h" viding an interengagement between the bearthe bar 2| is ooo vod o rre p n hoXaing members and a stationary portion'of the gonal cross section. In the practice of the inven-i bit body. tion 'the openings 20 may be conveniently 5 Further objects and advantages of the invenbroached to desired form from circular holes which have been previously drilled laterally through the legs l5 and I6.

Supported on the bar 2| in the spaces I! are series of bearing members 22, 23, and 24, on which relatively outer and inner cutter disks 25, 26, and 27 are rotatably carried, these cutter disks 25, 26, and 27 rotating on downwardly offset axes, as shown best in Fig. 2, by reason of the downwardly relatively offset placement of the bearing members 22, 23, and 24 on the supporting bar 2 I. In addition to being downwardly offset in the manner shown in Fig. 2, the bearing members 22, 23, and 24 are forwardly offset in the direction of rotation, as shown in Fig. 3, so that the cutter disks 25, 26, and 2? will be held in forwardly ofiset relationship to give the forward portions of the cutting edges 30, 3|, and 32 a desired lead and to prevent tracking of the following portions 33, 34, and 35 of such cutting edges 30, 3|, and 32 when the rotary disk bit is in operation.

A valuablefeature of my invention resides in the simple means for determining the relative operating positions of the cutter disks in the drill body. As previously described, the rugged supporting bar 2| is made of non-circular cross section so as to be non-rotatable in the legs I5 and Hi. In a similar manner, the openings 36 through thebearing members 22, 23, and 24 are made of corresponding non-circular cross section so thatthe bearing members will not rotate on the bar 2|. This makes possible the positive determination of the position of each bearing member 22, 23, or 24 as a result of placing theopenings 36 therein to give the desired positioning of the bearing members.

For instance, by upwardly offsetting a hole 36 in a bearing member such as 24, the placing of the bearing member on the supporting bar 2| will result in the axis or center of such bearing member being downwardly ofiset relative to the bar 2|; therefore, by vertically offsetting the openings 36 of the bearing members 22, 23, and 24 in a manner such as illustrated in Fig. 2, a desired progressive inwardly and downwardly offset relationship of these bearing members may be accomplished. In addition to this,

it is a feature of the invention to make the cutter.

disks 25, 26, and 2'! of such diameter that the respective lower portions 40, 4|, and 42 of the cutting edges thereof will be progressively offset downwardly from the extereme outer cutter disk 25 toward the extreme inner cutter disk 21 of each set of cutter disks, there being three disks 25, 26-, and 21 to each set in the present illustration of the invention, it being understood that in the practice of the invention a smaller or larger number of cutter disks may be employed inthe manufacture of smaller and larger sizes of bits, and it being further understood that the, offset relationship of the lower portions of the cutting edges may be increased or decreased to suit existing conditions.

The invention also includes simple means for locking the supporting bar 2| against lateral displacement in the legs l5 and 6, these locking means 44 in place, the pin portions 45 thereof serve as keys for preventing lateral movement of the bar 2|. Large size in these locking means is not required for the reason that in the operation of the bit there is substantially no force exerted which tends to displace the bar 2| from its operative position.

The rotary disk bit of my invention is especially equipped for operation on hard formations by teeth 50 formed in the peripheries of the cutters 25, 26, and 21, or in the peripheries of any selected number of these cutters as may be found advisable. To prevent tracking of the cutter teeth 50, the invention comprehends the making of teeth of diifering sizes in the cutters. Illustrative of this, in Fig. l I have shown large cutting teeth at 5| in one of the cutter disks, such as an outer cutter disk 25, smaller cutting teeth 52 in an intermediate cutter disk 26, and yet smaller teeth 53 in an inner cutter disk 21.

As shown in Fig. 5, a cutter disk 55 may be equipped with teeth 56, 51, and 58 which are all of different size and are so distributed that they will not track when the cutter disk 55 is rotated in cutting engagement with a formation.

Extending vertically downwardly from the main fluid passage M of the bit body H is a central fluid passage 60 which extends vertically and centrally through the center leg |5 to the lower end thereof, a part of this passage being formed by a vertical hole 6| which extends through the center of the bar 2|. The fluid passage 60 is in such position that it will discharge fluid directly against the central core portion formed in the formation being drilled by the cutter disks placed on each side of the center leg. l5, such discharge of fluid serving to displace or assist in displacing the central core portion during the drilling operation.

Extending downwardly and diagonally forwardly within the cutter body H are fluid passages 10 which are so positioned that they will direct flows of drilling fluid, as indicated by dotted lines 12, against the forward portions of the cutting edges of the cutter disks so as to keep these cutter disks clean and toassist in the removal of the cuttings by the flow of drilling fluid which, as previously stated, is generally in the form of a mud and water mixture.

Where exceptionally hard formations are encountered, it is desirable to move the inner cutter disks of the bit assembly as close to the center as possible so that substantially no core will be formed by the operation of the bit on the bottom of the hole.

In Fig. 6 I show my invention applied to a bit in which the center leg is foreshortened so that the inner cutter disks 78 may be placed close together on central bearing members" which are held in properly spaced positions by a spacing washer '18. In this form of the invention the supporting bar 19. extends between side legs 80 and is supported in working position by the engagement of its ends by the legs 80. The bar 19 is of such form that it will carry the forces imposed thereon during drilling operations without undue or harmful ilexure. Owing to the severe twisting strains which are applied to the inner cutters 16, they are preferably to be made of greater thickness than the intermediate and outer cutters BI and 82 which are supported on intermediate and outer bearing members 83 and 84.

In this form of the invention, the bar 19. is also non-rotatable and holds the bearing members I1, 83, and 84 non-rotatably' in working position. For the accomplishment of these effects=the bar'l9 may be made of non-circular cross section, such as hexagonal, and may be locked in regular'openings 85 of similar cross section by means of locking screws 86.

Relative to the form of bit shown in Fig 2,

it has been explained. that the positions of the bearing members for the cutter disks are determined by the positions of the openings in such bearing members through which the supporting bar extends, thereby making it possible in the design of the bit to 'establish'any' de-' sired plan of cutting engagement of the lower j portions of thefcutter disks to meet conditions which may be encountered in different formations. In Fig. 6, the lower edges of the cutter disks I5, 8|, and 82 are shown in substantially a straight line, this alignment varying from that shown in Figs. 1 and 2 and being accomplished by positioning the openings 81 of the bearing members 11, 83, and 84 so as to establish required axes of rotation for the cutter disks I5, BI, and 82.

It is a feature of this form of the device to extend a drilling fluid passage '88 substantially centrally therein through the central leg 15 so that a stream or jet of drilling fluid under pressure will be directed against the inner cutters It, thus preventing accumulation of cuttings on or between the inner cutters 10.

In the form of the invention shown in Fig. 6, diagonal passages 89 are provided for directing streams of drilling fluid toward the forward portions of the outer cutter disks Ill and 82, these diagonal passages 89 functioning in the same manner as the diagonal passages 10 of- Figs. 1 and 2.

The embodiment of the invention shown in Fig. 7 includes a bit body 90 having water'passages 92 and 93 therein. Extending through the inner leg 94 and outer legs 95 of the bit body 90 is a cylindrical supporting bar 96 which is restrained from lateral movement by locking pins 97.

Outer cutters 98 and inner cutters 99 are respectively mounted on outer and inner bearing members I and "H, the inner bearing members I 0| being forwardly. and downwardly axially offset relative to the outer bearing members I09, such axially offset positionsof the inner bearing members IOI being determined by the positions of the openings I02 therein. Although the axial positions of the bearing members are determined by the supporting bar 96, they, unlike the bearing members shown in the previous figures of the drawings, are not held from rotation by the supporting bar 98 which is of cylindrical form. Therefore, to prevent rotation of the bearing members, I have provided interengagement means between such bearing members and stationary parts of the bit body 90, such means of interengagement being shown in Fig. 7 as consisting of laterally extending ribs or keys I formed on the inner faces of the outer legs 95, these ribs or keys projecting into cooperating grooves or channels I06 in the outer bearing members I00, and ribs or keys I01 formed on the inner faces of the bearing members IOI, which ribs or keys extend into key-ways or slots I08 in the center leg 94.

If desired, additional interengagement may be provided between the pairs of outer and inner bearing members I00 and MI in the form of keys IIO projecting from the inner faces of the outer bearing members I00 into lateral key-ways III in the cooperating-faces of the inner bear-' ing members IOI. In the assembly oi the bit" structure shown in Fig. 7, the bearing members I00 and [DI ,having their respective cutter disks 98 and 99 mounted thereon are movedlaterally into positions between the inner leg 94 and the outer legs 95. The supporting bar 96 is then inserted through the openings in the legs 94 and 95 and the openings of the bearing members and is locked against lateral movement by the locking means 91. I

In this form of the invention the bearing members are positively held against rotation by interengagement-With stationary portions of the bit body and are positively held in operating position by the supporting bar 96. The bearing members and the cutter disks may be readily removed when worn and replaced by new bearing members and cutter disks with a minimum expenditure of labor.

I have herein shown simple and practical forms of my invention, but it is recognized that certain parts or elements thereof are representative of other parts, elements, or structures which may be employed in substantially the same manner to accomplish substantially the same results; therefore, it is to be understood that the invention is not to be limited to the details disclosed herein but shall have the scope set forth in the following claims.

I claim as my invention:

1. A rotary bit of the character described,

including: a bit body adapted for attachment to a string of drill pipe, said bit body having a downwardly extending center leg and diametrally opposing side legs; a bar extending laterally through said legs, said bar being nonrotatable in said legs; means for locking said bar in such laterally extending position; bearing members supported on said bar in the spaces between said center and said side legs, said bearing members being non-rotatable on said bar and having openings to receive said bar so placed that said bearing members will be progressively downwardly oifset from the outer bearing members toward the inner bearing members; and cutter disks supported on said bearing members.

2. A rotary bit of the character described, including: a bit body adapted for attachment to a string of drill pipe, said bit body having a downwardly extending center leg and diametrally opposing side legs; a bar extending laterally through said legs; means for locking said bar in such laterally extending position; bearing members supported on said bar in the spaces between said center and said side legs; and,

cutter disks supported on said bearing members, there being a central fluid passage leading downwardly through said center leg andthrough said bar for delivering a flow of fluid against the central core formed by said cutter disks when said bit is operated.

3. A rotary bit of the character described, including: a bit body adapted for attachment to a string of drill pipe, said bit body having a downwardly extending center leg and diametrally opposing side legs; a bar extending laterally through said legs, said bar being non-rotatable in said legs; means for locking said bar in such laterally extending position; bearing members supported on said bar in the spaces between said center and said side legs, said bearing members being non-rotatable on said bar and having openings to receive said bar so placed as to determine the relative axial positions of said bearing members; and cutter disks supported on said bearing members, there being a central fluid passage leading downwardly through said center leg and through said bar for delivering a flow of fluid against the central core formed by said cutter disks when said bit is operated.

4. A rotary bit of the character described, including: a-bit body adapted for attachment to a string of drill pipe, said bit body having a downwardly extending center leg and diametrally opposed side legs, there being aligned, laterally directed non-circular openings through the lower ends of said legs; a; ruggedsupporti'ng bar extended through .siaid openings, said supporting bar having a cross section corresponding to said openings so as to be non-rotatable therein; cutter disks assuming tangential positions in the spaces between said center leg and said side legs; and bearing members for supporting said cutter disks, saidlbearing members having penings therein corresponding to the cross sectionof said supporting bar and so positioned relative to the centers thereof as to give a vertical- 1y offset positioningof said bearing members when said bearing members are in place on said supportingbar.

. JAMES W. SPERRY. 

